Tobacco having an oxadiazole additive



United States Patent 3,410,277 TOBACCO HAVING AN OXADIAZOLE ADDITIVE Tore Dalhamn, Stockholm, Sweden, assignor to P. Lorilllard Company, New York, N.Y., a corporation of New ersey No Drawing. Filed Aug. 10, 1966, Ser. No. 571,419 4 Claims. (Cl. 131-17) This invention is related to improvements in tobacco products, and in particular it relates to novel smoking tobacco products, such as cigarettes, cigars, pipe tobacco and the like having improved physiological properties.

In the respiratory system, the mucous membranes of the trachea and bronchea are covered with minute hairs known as cilia which rhythmically beat upwardly away from the lungs. These cilia trap inhaled foreign particles and by means of their motion raise them to the pharynx.

It has been established that tobacco smoke inhibits the activity of the ciliated, mucous-secreting epithelium tissues of the respiratory tract of experimental animals. When the activity of the cilia is inhibited by tobacco smoke, particles, such as tobacco tar particles, pass by the less active or quiescent cilia and collect and accumulate in the lungs and others of the respiratory tract.

During non-smoking periods the original activity of the cilia is regained, and some, but not necessarily all, of the foreign matter entering the respiratory tract is dislodged. It is apparent that if the cilia could remain active during smoking, a substantially increased proportion of the tobacco smoke particles would be discharged by the cilia. The quantity of particles remaining in the respiratory tract would be correspondingly reduced.

In accordance with the present invention it has been found that the addition of certain oxadiazole compounds to the tobacco exerts an anticiliastatic action which antagonizes the inhibiting effects of tobacco smoke on the ciliary motility in the respiratory tract. Oxadiazoles useful in the present invention have the formula wherein X is hydrogen, a halogen or a lower alkyl having from one to four carbon atoms and R is an amino radical of the formula (CH NR R wherein n is from O to 4, and R and R are-alkyl or alkylol radicals having from 1 to 4 carbon atoms.

The oxadiazoles of the present invention are used in the forms of their neutral addition salts with pharmacologically innocuous acids. Preferred acids are organic compounds such as citric, acetic, tartaric, gluconic, etc. Other pharmaceutically acceptable acids which may be used include the strong mineral acids such as sulphuric acid, hydrochloric acid, hydrobromic acid and methanesulphonic acid. It will be understood, of course, that the foregoing pharmacologically acceptable acids are representative only of those which can be used within the scope of the present invention.

Tobacco is treated in accordance with the present invention by applying a solution of a salt of one of the above-described oxadiazoles to the tobacco leaf after it has been dried and converted from fresh green leaf into smoking tobacco. The treated tobacco may contain from about 1% to about by weight of the oxadiazole. Preferably, about 3% to 8% thereof is employed. The solution from which the oxadiazole is applied may be either aqueous or organic. Alcoholic solutions, such as methanol, ethanol or propanol are particularly preferred since these solvents are volatile and can be readily removed after application of the oxadiazole.

Following treatment of the tobacco with the oxadiazole 3,410,277 Patented Nov. 12, 1968 solution, the solvent is evaporated and the treated leaf is stored in order to equilibrate it to the proper moisture content. It is then prepared into cigarettes or other tobacco products in accordance with standard procedures.

By way of illustration a typical tobacco is prepared by adding 5% by weight of 3-phenyl-5-diethylaminoethyl- 1,2,4-oxadiazole citrate to a commercial blend of cigarette tobacco. The material was added to the tobacco as a saturated methanol solution. After evaporation of the methanol under ambient conditions, the tobacco was stored until it was equilibrated to the proper moisture content. Thereafter cigarettes were prepared with the usual manufacturing machinery. Filter and non-filter mm. sample cigarettes were prepared, as well as control cigarettes of similar construction from tobacco to which no oxadiazole had been added.

Tests were performed to measure the anticiliastatic effect of the oxadiazole which had been added to the cigarettes. These tests were performed as described in the paper by Dalhamn entitled A Method for Studying the Effect of Gases and Dusts on Ciliary Activity in Living Animals, appearing in Inhaled Particles and Vapour, Pergamon Press 1961.

Briefly summarised, the tests were carried out by performing a tracheotomy on anaesthized cats. An aperture was placed in the trachea and enclosed by a diaphragm by means of which a microscope lens could be mounted to observe the ciliary movement within the trachea. The microscope was adapted to take motion pictures of the ciliary activity.

The cat was placed in a respirator thereby to control breathing to an even rate, and the cat was then exposed to periodic inhalations of cigarette smoke (one inhalation in every four breaths). The foregoing test is described in greater detail in the above-mentioned paper.

By means of the foregoing test, the number of puffs of tobacco smoke which were necessary until ciliastasis occurred were measured using the smoke from filter-tip cigarettes in which the tobacco had been treated with 3-phenyl- S-diethylaminoethyl-1,2,4-oxadiazole citrate and compared with the number of puffs until ciliastasis when employing cigarette smoke from cigarettes made by untreated tobacco. The results are set forth in the following table:

A statistical treatment of the foregoing data shows that the decrease in the ciliastatic effect of tobacco caused by treating the tobacco with the oxadiazole compound is highly significant.

Results analogous to the foregoing may similarly be obtained by treating tobacco with each of the following oxadiazole compounds at the following level.

I claim:

1. A smoking tobacco product consisting essentially of tobacco and a pharmacologically acceptable salt of an oxadiazole of the formula N=GR wherein X is a member of the group consisting of hydrogen, halogen and lower alkyl having from 1 to 4 carbon atoms, and R is an amino radical of the formula wherein n is an integer from 0 to 4 and R and R are each selected from the group consisting of alkyl and alkylol having from one to four carbon atoms, the amount of said oxadiazole being suificient to antagonize at least partially the ciliastatic eifect of tobacco smoke.

2. A smoking tobacco product according to claim 1 wherein the amount of said oxadiazole is between 1% and 10% by weight of the tobacco.

3. A smoking tobacco product according to claim 1 wherein said oxadiazole has been incorporated into the tobacco by solvent impregnation.

4. A smoking tobacco product according to claim 1 wherein said oxadiazole is 3-phenyl-S-diethylaminoethyl- 1,2,4-oxadiazole citrate.

MELVIN D. REIN, Primary Examiner. 

1. A SMOKING TOBACCO PRODUCT CONSISTING ESSENTIALLY OF TOBACCO AND A PHARMACOLOGICALLY ACCEPTABLE SALT OF AN OXADIAZOLE OF THE FORMULA 